fast-twitch
adjective
: of, relating to, or being muscle fiber that contracts quickly especially during brief high-intensity physical activity requiring strength compare slow-twitch
Examples of fast-twitch in a Sentence
Recent Examples on the Web
For examples, men tend to have more muscle mass, a larger store of fast-twitch muscle fibers, and a higher VO2 max, or the maximum rate of oxygen intake.
—
Mia Cathell, The Washington Examiner, 27 Apr. 2025
During intense exercise, the pH in your fast-twitch muscle fibers (which seem to be particularly susceptible to hydrogen ion buildup) can drop from around 7.0 to 6.0.
—Alex Hutchinson, Outside Online, 24 Apr. 2025
It is largely driven by the loss of fast-twitch muscle fibers—responsible for explosive movements—and declines in reactivity, or the ability to respond quickly to a threat, such as a misstep on uneven ground.
—Jesse Pines, Forbes.com, 8 Apr. 2025
In addition, explosive exercises like sprinting and skipping help retain fast-twitch muscle fibers, crucial for power and reaction time.
—Jesse Pines, Forbes, 24 Mar. 2025
For example, a male in their 20s with a large percentage of fast-twitch muscle fibers (those that respond to growth the easiest) could gain lean muscle mass at a rate of two pounds per month.
—Sherri Gordon, Health, 18 Mar. 2025
Keep going: Challenge your fast-twitch muscle fibers by incorporating sprints.
—Jen Murphy, New York Times, 10 Feb. 2025
These machines are great for casual pastimes and video streaming, not for fast-twitch fragging.
—PCMAG, 17 Jan. 2025
Some people may have a higher proportion of fast-twitch muscle fibers with greater growth potential.
—Alyssa Hui-Anderson, Verywell Health, 25 Nov. 2024
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Mia Cathell, The Washington Examiner, 27 Apr. 2025
During intense exercise, the pH in your fast-twitch muscle fibers (which seem to be particularly susceptible to hydrogen ion buildup) can drop from around 7.0 to 6.0.
—Alex Hutchinson, Outside Online, 24 Apr. 2025
It is largely driven by the loss of fast-twitch muscle fibers—responsible for explosive movements—and declines in reactivity, or the ability to respond quickly to a threat, such as a misstep on uneven ground.
—Jesse Pines, Forbes.com, 8 Apr. 2025
In addition, explosive exercises like sprinting and skipping help retain fast-twitch muscle fibers, crucial for power and reaction time.
—Jesse Pines, Forbes, 24 Mar. 2025
For example, a male in their 20s with a large percentage of fast-twitch muscle fibers (those that respond to growth the easiest) could gain lean muscle mass at a rate of two pounds per month.
—Sherri Gordon, Health, 18 Mar. 2025
Keep going: Challenge your fast-twitch muscle fibers by incorporating sprints.
—Jen Murphy, New York Times, 10 Feb. 2025
These machines are great for casual pastimes and video streaming, not for fast-twitch fragging.
—PCMAG, 17 Jan. 2025
Some people may have a higher proportion of fast-twitch muscle fibers with greater growth potential.
—Alyssa Hui-Anderson, Verywell Health, 25 Nov. 2024
Cite this Entry
“Fast-twitch.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fast-twitch. Accessed 21 May. 2025.
Copy CitationMedical Definition
fast-twitch
adjective
: of, relating to, or being muscle fiber that contracts quickly especially during brief high-intensity physical activity requiring strength compare slow-twitch
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